JP2002240080A - Method for producing injection-molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an injection-molded article which can appropriately discharge air in the cavity of a mold outside the cavity without forming air vents in the parting surfaces of the mold and mold the article, so that the article can be discharged easily from the cavity even when the article is molded by using a hard material. SOLUTION: A sheet-shaped member 3 is held between the parting surfaces 21a and 22a which the mold clamped, and part of the member 3 is arranged at the position of a cavity 22c. Next, a molten resin for molding the injection- molded article 1 is injected into the cavity 22c, part of the article 1 is stuck to the member 3 at the position of the cavity 22c, and air in the cavity 22c is discharged outside the cavity 22c through voids generated by the interface mismatching between the parting surfaces 21a and 22a and the member 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an injection-molded article, and more particularly to an injection-molding method capable of easily improving the air bleeding property when a molten resin for molding an injection-molded article is injected into the cavity in a mold. The present invention relates to a method for manufacturing a product.

[0002]

2. Description of the Related Art Conventionally, a resin molded article has been molded by an injection molding method. The injection molding method is to obtain a resin molded product by injecting and filling a molten resin for molding a resin molded product (injection molded product) into a cavity in a mold. In order to completely fill the cavity with the molten resin, it is necessary to efficiently discharge air or volatile gas (hereinafter referred to as “air”) in the cavity to the outside of the cavity. This is because, when the air in the cavity is not sufficiently discharged during the injection of the molten resin and the air remains in the cavity, a short shot (insufficient filling) occurs due to the remaining air, or the remaining air is generated. This is because the molten resin in the cavity may be compressed to a high temperature to cause burning or burning of the resin molded product.

[0003] In order to eliminate such molding defects, conventionally, for example, an air vent for discharging residual air is provided on a parting surface of a mold. When the air vent is provided in this manner, the air in the cavity is efficiently discharged out of the cavity via the air vent when the molten resin is injected into the cavity.

[0004]

However, when the air vent is formed on the parting surface of the mold as described above,
It is necessary to fine-tune the depth of the air vent on the parting surface according to the molding conditions such as the material of the molten resin injected into the cavity and the shape of the resin molded product. There was a problem that it would.

[0005] That is, for example, if the depth of the air vent is too shallow as compared with the molding conditions described above, the efficiency of discharging air from the cavity is deteriorated, and short shots and burning are promoted. If the depth is too deep, the molten resin flows into the air vent and burrs are generated, so it takes time and effort to finely adjust the depth of the air vent integrated with the mold. Only the cost required for forming the mold is excessively increased.

On the other hand, resin molded articles formed by the injection molding method include those made of various materials. For example, low-hardness materials such as agglomerated resin (specifically,
It may be made of a low-hardness material having a hardness of 40 or less in JISA type hardness (specifically, A type hardness of JIS K6253). Incidentally, the agglomerated resin referred to here is a resin in a state where fluidity is lost due to inclusion of an oil component in the interstices of the network structure of the base polymer.

However, when a resin molded article is molded using such a low hardness material, there is a problem that it is difficult to remove the resin molded article from the cavity after molding due to the material characteristics of the low hardness material. . In other words, as a method of taking out the resin molded product from the cavity after the molten resin injected into the cavity is cooled and solidified, there is a method of projecting the resin molded product in the cavity to the outside of the cavity by using a protruding pin or air pressure. When the resin molded product is made of a low-hardness material, even if the resin molded product is pressed with a protruding pin or the like, only the pressed portion is greatly deformed, and the direction in which the resin molded product is projected (from the mold). There was a problem that the falling direction was not stable. In particular, when the resin molded article is made of the agglomerated resin, such a problem has become more apparent due to the tackiness of the agglomerated resin. still,
A method of directly picking out the resin molded product with an arm member or the like and removing it is also conceivable.However, if the resin molded product has adhesiveness on the surface like the agglomerated resin, after picking the injection molded product with the arm member etc. There is a problem that even if the user tries to separate them, they may stick to the arm member or the like and do not separate, and when picked up with the arm member or the like, dirt adheres to the surface of the resin molded product.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to allow air in a cavity of a mold to be suitably discharged from the cavity without providing an air vent on a parting surface of the mold. It is possible to discharge the injection molded product so that the injection molded product can be easily removed from the cavity even when the injection molded product is molded using a low hardness material. It is to provide a manufacturing method.

[0009]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, a method of manufacturing an injection-molded article according to the first aspect of the present invention provides a method of manufacturing an injection-molded article, in which both a fixed mold side and a movable mold side are parted. A method of manufacturing an injection-molded product, in which a molded resin is molded by injecting a molten resin into a cavity of a mold after being clamped on a surface, wherein a sheet-shaped member made of a material different from the molten resin is used. A sheet-shaped member clamping step of clamping a part of the sheet-shaped member at the cavity position when the mold is clamped by the parting surface of the mold, and after the sheet-shaped member clamping step, The molten resin is injected into the cavity, a part of the molten resin filled in the cavity is attached to the sheet-like member at the cavity position complementarily, and the air in the cavity is moved forward. An injection step of discharging to the outside through a gap generated by an interface mismatch between the sheet-like member and the parting surface sandwiched between the parting surfaces, and cooling and solidification in the cavity after the injection step And removing the molded article and the sheet-shaped member by opening the mold and taking out the molded article.

In the method for producing an injection-molded article of the present invention, air or volatile gas (hereinafter simply referred to as "air") in the cavity when the molten resin is injected into the cavity of the mold.
Is discharged through the gap due to the interface mismatch between the sheet-shaped member and the parting surface of the mold, so that an air vent is provided on the parting surface of the mold and the depth of the air vent is provided. Even if the method of finely adjusting the temperature is not taken, the discharge of air in the cavity when the molten resin is injected can be adjusted, and the discharge can be made appropriate.

That is, by changing the sheet-like member sandwiched between the parting surfaces of the mold, the surface shape, surface roughness, etc. of the sheet-like member are changed to change the size of the gap due to the interface mismatch. If it does, even if it does not form an air vent on the parting surface of the mold, it is possible to easily adjust the discharge efficiency of the air in the cavity that is discharged out of the cavity when the molten resin is injected. It is also possible to adjust the discharge efficiency to a suitable one.

According to the present invention, an air vent is formed on the parting surface of the mold to discharge air in the cavity to the outside of the mold, so that fine adjustment of the groove depth of the air vent is not required. Only, it is possible to reduce the cost for forming the mold. As a mode of forming a gap between the sheet-like member and the parting surface due to the interface mismatch between the two, the shape at the contact portion between the two may be inconsistent or the surface roughness of the portion may cause the gap between the two. Any material may be used as long as it creates a void. Accordingly, for example, when the sheet-like member is sandwiched between the parting surfaces by increasing the surface roughness of the sheet-like member relatively (for example, by increasing the surface roughness of the parting surface). It may be configured such that a gap is formed between the sheet-shaped member and the parting surface, or a groove (unevenness) that can function as an air vent is formed in advance on the surface of the sheet-shaped member, and the sheet-shaped member is formed. The groove may function as an air vent when the member is sandwiched between the parting surfaces. And as a form which provides a groove | channel (irregularity) on the surface of a sheet-like member as mentioned above, a groove | channel (irregularity) may be provided by additional processing on the surface of a sheet-like member. In another embodiment, for example, a plurality of other sheet pieces (hereinafter, also referred to as “stacking sheet pieces”) are spaced from each other on the surface of one sheet piece (hereinafter, also referred to as “main sheet piece”). A sheet-like member is formed by placing, arranging and laminating, and a space between the plurality of laminating sheet pieces on the main sheet piece (a portion where the surface of the main sheet piece is exposed) functions as a groove (irregularity) as an air vent. It may be the one that causes it. This aspect is suitably applied to a case where a sheet-like member is formed using a sheet piece having a relatively small surface roughness (a main sheet piece and a sheet piece for lamination).

On the other hand, in the present invention, when the mold is clamped, a part of the sheet-like member is arranged in the cavity portion, and when the molten resin is injected, a part of the molten resin is removed from the sheet-like member. In this case, even if the injection-molded product (molten resin) is made of a low-hardness material, the injection-molded product can be easily removed from the cavity.

That is, first, the method of removing the injection molded product and the sheet-like member in the molded product removing step according to the present invention is not limited to a predetermined method, and may be any method. However, when the injection-molded article is made of a low-hardness material, as described in the section of “Problems to be Solved by the Invention”, the injection-molded article is cavity If the injection-molded product has adhesiveness on the surface even if the method of picking it out directly with an arm member etc. does not protrude in a stable direction from it, the injection-molded product will not stick to the arm member etc. There was a problem that there was a case.

On the other hand, in the present invention, a part of the injected molten resin is complementarily adhered to the portion in the cavity of the sheet-like member as described above, so that the cooled and solidified injection-molded article and the sheet-like member are combined. At the time of removal, the injection-molded product and the sheet-like member are integrated.

Therefore, according to the present invention, even if the injection-molded article is made of a low-hardness material, for example, if a method of picking and pulling the sheet-like member in the molded article taking-out step is adopted, The injection molded product integrated with the shaped member can be easily taken out, and the injection molded product can be easily taken out. That is, according to the present invention, even when an injection molded article is molded using a low hardness material, the injection molded article can be molded so that the injection molded article can be easily taken out of the cavity.

When the molten resin is injected, a part of the molten resin is adhered to the sheet-like member at the cavity position in a complementary manner, when the cooled and solidified injection-molded article and the sheet-like member are taken out. Any material may be used as long as the injection-molded article and the sheet-like member are adhered complementarily so as to be integrated.

Accordingly, for example, a sheet member made of a material that does not melt upon contact with the molten resin (a sheet member having a melting point higher than the melting point of the resin forming the injection molded article, a sheet member made of a non-thermoplastic sheet, etc.) The injection molded article and the sheet-shaped member may be integrated by solidifying in a state in which a part of the molten resin enters the fine irregularities on the surface of the molten resin, or the injected molten resin The injection-molded article and the sheet-shaped member may be integrated by welding the and the sheet-shaped member to each other.

In the former of the above two embodiments, for example, the unevenness (surface roughness) of the surface of the sheet-like member to which the molten resin adheres (enters) complementarily is made relatively small. After the injection molded article is molded, it is possible to construct the injection molded article so that it can be easily peeled off from the sheet-like member by the operator's hand. In such a case, the packing and transportation of the injection molded article can be performed. In some cases, such as when the injection molded article and the sheet-shaped member are integrated with each other, the injection molding article and the sheet-shaped member are separated from each other, for example, when the injection molded article is actually used. It is also possible to take.

In the latter embodiment, since the injection molded article and the sheet-like member are stably fixed by welding, not only when the injection molded article is packed and transported but also when it is actually used. Also, it is possible to adopt a usage mode in which the injection molded article and the sheet-shaped member are integrated.

On the other hand, there is no particular limitation on the part of the sheet-like member to which the molten resin is adhered complementarily when the molten resin is injected. The molten resin may be adhered complementarily, but may be the one described in claim 2.

That is, in the method for manufacturing an injection-molded article according to the second aspect, in the manufacturing method according to the first aspect, at the time of the sheet-like member holding step, the sheet-like member is located at the cavity position. The arranged portion is arranged along the parting surface, and at the time of the injection step, one surface of the sheet-like member at the cavity position (one surface of the sheet-like member arranged along the parting surface) ) Is characterized in that the molten resin is adhered complementarily only to the surface on the side opposite to the above.

According to the method of manufacturing an injection-molded article according to the second aspect, for example, even if the injection-molded article has an adhesive property on the surface of the agglomerated resin or the like, it can be formed after molding. The injection molded article can be easily handled. In other words, for example, when a plurality of injection molded products having adhesiveness on the surface are molded, and the plurality of injection molded products are packed or the like, in order to prevent the respective injection molded products from sticking to each other, It is necessary to provide a partition between the injection-molded articles, but if the injection-molded article is molded by making the molten resin adhere to only one side of the sheet-shaped member as described in claim 2, the sheet-shaped member is formed. (Specifically, the surface of the sheet-shaped member on which the molten resin (injection molded product) is not complementarily attached)
Can function as a partition so that a plurality of injection molded products can be packed and the like, and handling of the injection molded products becomes easy.

According to a third aspect of the present invention, there is provided a method of manufacturing an injection-molded article according to the first or second aspect, wherein the sheet-like member is removed after the step of removing the molded article. Moved with respect to the mold, in the sheet-shaped member holding step, the mold-opened part different from the part of the sheet-shaped member arranged between the mold fixed side and the mold moving side. A sheet-like member moving step disposed between the mold fixed side and the mold moving side, and after the sheet-like member moving step, the sheet-like member clamping step;
The method is characterized by including the same steps as the injection step and the molded article removal step.

According to the method for manufacturing an injection-molded article according to the third aspect, operations such as packing of the injection-molded article when a plurality of injection-molded articles are manufactured can be efficiently performed. That is, first, as a method of manufacturing a plurality of injection molded products based on the manufacturing method of the present invention (claim 1), for example, an injection molded product integrated with a sheet member is used. The sheet-like member may be replaced with another sheet-like member each time one is manufactured. When such a method is employed, the sheet-like member integrated with the injection-molded product is provided one by one without cutting the sheet-like member when packing the molded injection-molded product. Etc. can be stored.

On the other hand, according to the manufacturing method of the third aspect, the sheet-shaped member is moved after the injection-molded article and the sheet-shaped member are removed from the cavity of the mold, and the sheet-shaped member is moved before the movement of the sheet-shaped member. Another part of the sheet-like member, which was not arranged between the mold fixing side and the mold moving side in the sheet-like member holding step, was arranged between the mold fixing side and the mold moving side. Then, since the same processes as the above-described steps (sheet-like member holding step, injection step, and molded article removing step) for manufacturing an injection-molded article are performed, a plurality of injection moldings are performed by repeating such a series of steps. It becomes possible to mold a product, and after molding a plurality of injection molded products, a plurality of injection molded products are integrated with one sheet-shaped member.

According to the manufacturing method of the present invention, a plurality of injection molded articles integrated with one sheet member can be obtained. When packing, etc., a plurality of injection-molded products can be handled as one unit via a sheet-shaped member, so that operations such as packing of injection-molded products can be performed efficiently.

In the case of mass-producing a large number of injection-molded articles, in the sheet-like member moving step, when the sheet-like member is moved, positioning after the movement of the sheet-like member is performed. It is desirable that the configuration be such that a molten resin (injection molded article) can be attached to a desired position in a complementary manner. Although there is no particular limitation on the manner of performing the positioning after the movement of the sheet-like member in this way, for example, the method described in claim 4 may be used.

According to a fourth aspect of the present invention, in the method of manufacturing an injection-molded article according to the third aspect, a positioning mark is formed on the sheet-like member, and the sheet-like member moves. In the step, the positioning after the movement of the sheet-like member is performed by positioning the positioning mark.

According to the method of manufacturing an injection-molded article according to the fourth aspect, the sheet-like member is moved in the sheet-like member moving step by a simple method of positioning the positioning mark on the sheet-like member. Since the positioning of the sheet-like member after the sheet-like member can be executed, the position where the molten resin (injection molded article) is attached to the sheet-like member can be easily set to a desired position. Therefore, for example, even when mass-producing a large number of injection-molded products, the position of the injection-molded products with respect to the sheet-shaped member can be stably determined, so that the effect of suitably mass-producing the injection-molded products is obtained.

Next, a method of manufacturing an injection-molded article according to claim 5 is characterized in that, in the method of manufacturing according to claim 3 or 4, the sheet-shaped member is a tape-shaped member. And According to the method of manufacturing an injection-molded article according to the fifth aspect, since the sheet-like member has a tape-like (in other words, a band-like or long-like) shape, the sheet-like member in the sheet-like member moving step. The moving direction of the member can be reliably ensured in the longitudinal direction of the sheet-shaped member, and a plurality of injection molded products can be efficiently manufactured.

That is, first, as described above (claim 3),
When manufacturing a plurality of injection-molded products by repeating each process of the sheet-shaped member clamping process, the injection process, the molded product removal process, and the sheet-shaped member moving process a plurality of times, for example, according to the shape of the sheet-shaped member, etc. Thus, the moving direction of the sheet member in each sheet member moving step may be different.

On the other hand, according to the aspect of the present invention, since the sheet-like member has a tape-like shape, the moving direction of the sheet-like member in each sheet-like member moving step is changed to the direction of the sheet-like member. It can be ensured in the longitudinal direction. Therefore, the movement efficiency of the sheet member (and hence the efficiency of manufacturing the injection molded product) can be improved by the amount by which the moving direction of the sheet member can be kept constant, and the mechanism for moving the sheet member can be realized at low cost. . That is, according to the manufacturing method of the fifth aspect, it is possible to efficiently manufacture a plurality of injection molded articles corresponding to the length of the sheet-shaped member in the longitudinal direction.

If the sheet-like member has such a tape-like shape, the sheet-like member in which a plurality of injection-molded articles are stuck together is wound (in other words, the sheet-like member is wound). When the sheet-like member is wound so that the portion extending in the longitudinal direction of the sheet-like member is arranged along the winding direction while the member functions as a partition for each injection molded article), a plurality of injections are performed. The molded article can be suitably packaged and shipped together with the sheet member.

The material of the sheet-like member is not particularly limited as long as the sheet-like member can exert the above-mentioned effects. For example, paper, cloth, resin (resin) As for the material and the like, a graining process (a process of providing an uneven surface on the surface) or a boring process or the like to achieve the above-described effect by performing a punching process or the like as necessary can be considered.

Next, according to a sixth aspect of the present invention, in the method for manufacturing an injection-molded article according to any one of the first to fifth aspects, the hardness of the injection-molded article is JIS A
It is characterized in that the mold hardness (specifically, A-type hardness according to JIS K6253) is 40 or less.

The method of manufacturing an injection-molded article according to claim 6 shows a specific embodiment of the material (hardness) of the injection-molded article (molten resin). The same operation and effect as the operation and effect by 1 etc. can be obtained. still,
The material which can be used as the injection molded article (molten resin) according to claim 6 is a polyolefin-based elastomer, a polystyrene (PS) -based elastomer, or a thermosetting resin having a JIS A type hardness of 40 or less. Examples include a plastic polyurethane (TPU) -based elastomer, an unsaturated polyester (UP) -based elastomer, a styrene-ethylene-butylene-styrene block copolymer (SEBS) -based elastomer, and an agglomerated resin.

In the present invention, the agglomerated resin refers to a resin component as a base polymer cross-linked with each other to form a network-like structure, and an oil component (fluidity) is formed in a gap of the network-like structure. Component) and loses its fluidity as a whole to form an agglomerate.

Here, as the base polymer in the agglomerated resin, for example, styrene type, ester type,
Various thermoplastic elastomers such as amides and urethanes, and their hydrogenated and modified products, or styrene, ABS, olefin, vinyl chloride, acrylate, methacrylate, and carbonate Thermoplastic resins such as phenolic, acetal-based, amide-based, halogenated polyether-based, halogenated olefin-based, cellulose-based, vinylidene-based, vinylbutyral-based, and alkylene oxide-based resins, and rubber-modified products of these resins. . These various thermoplastic polymer organic materials may be used alone or as a blend of two or more.

In general, a liquid or liquid material at room temperature is suitably used as the oil component. Either hydrophilic or hydrophobic softeners can be used, and various rubber or resin softeners such as mineral oils, vegetable oils, and synthetic oils can be used. One of these softeners may be used alone, or two or more of them may be used in combination as long as they have good compatibility with each other. Also, the greater the amount of oil added, the lower the hardness of the agglomerated resin, so it may be adjusted to a desired hardness.

Next, according to a seventh aspect of the present invention, there is provided a method for manufacturing an injection-molded article according to any one of the first to sixth aspects, further comprising a recess corresponding to the shape of the injection-molded article. A cover member is prepared, and after the molded article removing step, a cover member attaching step of covering the injection molded article with the cover member so that the injection molded article is accommodated in the concave portion is provided.

According to the method of manufacturing an injection-molded product according to the seventh aspect, after the production by the manufacturing method, the surface of the injection-molded product may be scratched by another article colliding with the injection-molded product. In addition, it is possible to reliably prevent the surface of the injection molded product from being stained due to foreign matter adhering to the injection molded product.

When the cover member is put on the injection molded product in the cover member mounting step, the cover member is bonded to the sheet member in order to prevent the cover member from falling off the injection molded product and the sheet member. It is desirable to fix by doing the same. In the above description,
Although the term agglomerate was used, the agglomerate is sometimes called a gel and these two terms are interchangeable equivalent terms.

[0044]

Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, the injection-molded article 1 is made of a styrenic or urethane-based agglomerated resin, and as shown in FIG. It is mass-produced in a state where it is attached to the surface 3a at a constant interval.

The sheet member 3 is made of plain paper (PPC paper,
It is a tape-shaped member made of a paper material such as general high-quality paper), a cloth material such as a nonwoven fabric, a foamed resin such as a sponge material, and one end of the sheet-shaped member 3 is wound around the core material 7. ing. In the vicinity of both ends in the width direction (X direction in the drawing) on the surface of the sheet member 3, the sheet member 3
The plurality of through-holes 5a and 5b as positioning marks are placed at regular intervals along the longitudinal direction (Y direction in the drawing) of
Is provided.

Next, the configuration of a mold and the like for molding the injection molded article 1 will be described with reference to FIG. As shown in FIG. 2, in the present embodiment, a mold 20 for molding the injection molded article 1 includes a mold movable section 21 (mold moving side) and a mold fixing section 22 (mold fixing side). And the mold movable part 21
Are configured to be movable in the directions A and A ′ shown in FIG. 2 by a driving force obtained from a pressurizing cylinder (not shown). In the mold movable section 21, the parting surface 21a which is the surface on the mold fixing section 22 side is a flat surface, and in the mold fixing section 22, the parting surface 22a which is the surface on the mold movable section 21 side. In addition, when the mold movable part 21 moves to the mold fixing part 22 side and is clamped by both parting surfaces 21a, 22a, a hollow part (cavity 22) for molding the injection molded product 1 is formed.
The recess 22b is formed so as to be as shown in FIG. The cavity 22 is located on both parting surfaces 21a and 22a.
There is no well-known air vent for discharging the air in the cavity 22c to the outside of the cavity 22c when the molten resin for molding the injection-molded article 1 is injected into the c (concave portion 22b). Although not shown in FIG. 2,
A sprue or a runner is formed inside the mold fixing portion 22 to allow the molten resin for molding the injection molded product 1 injected from the nozzle of the heating cylinder device of the injection molding machine to flow into the recessed portion 22b. I have.

As shown in FIG. 2, in the present embodiment, prior to the molding of the injection molded article 1, the sheet-like member 3 is disposed between the two parting surfaces 21a, 22b that are spaced apart. . Specifically, first, although not shown in FIG. 2, the core member 7 is rotatably supported as a rotation shaft extending in the X direction at a location above the mold 20. The sheet-like member 3 fed downward from the material 7 is disposed between the two parting surfaces 21a and 22a so that the two parting surfaces 21a and 22a and the surface of the sheet-like member 3 are parallel to each other. The central portion of the portion of the sheet-like member 3 disposed between the surfaces 21a and 22a is a concave portion 22.
b.

When the sheet-like member 3 is arranged as described above, a part of the through-hole 5 in the sheet-like member 3 is formed.
Projection pieces (not shown) for feeding the sheet-like member are passed through a and 5b. That is, first, in the vicinity of the sheet-like member 3 (for example, in the vicinity of the place where the core material 7 is supported as described above), similarly to the case of the core material 7, the rotation axis is oriented around the X direction. A rotatable gear (not shown) is provided, and a plurality of protrusions are provided on the outer peripheral surface of the gear so as to be able to pass through the through holes 5a and 5b. When the sheet-like member 3 is arranged as described above, the projecting piece of the above-described gear is passed through some of the through holes 5a and 5b in a portion of the sheet-like member 3 that is fed out from the core member 7. so,
The positioning of the sheet-shaped member 3 with respect to the mold 20 is performed. That is, the through-holes 5a and 5b are formed along the longitudinal direction of the sheet-like member 3 with an interval corresponding to the pitch of the individual projecting pieces on the outer peripheral surface of the gear described above. Is positioned below the core member 7 by the rotation of the gear and the positioning of the through holes 5a and 5b through which the protruding pieces of the gear pass, and the positioning is performed at a position corresponding to the rotation angle of the gear. Is done.

Next, a method for manufacturing the injection molded article 1 of this embodiment will be specifically described. First, the mold movable section 21 is moved in the direction A (the direction toward the mold fixing section 22), whereby the mold is clamped on both parting surfaces 21a and 22a, and a sheet is placed between the parting surfaces 21a and 22a. The shape member 3 is sandwiched. At this time, the concave portion 22 of the mold fixing portion 22
The portion of the sheet-like member 3 opposed to the position b is located at the position of the cavity 22c formed by the recess 22b. In this embodiment, since the parting surface 21a is a flat surface as described above, when the mold is clamped on both parting surfaces 21a and 22a as described above, the sheet disposed at the position of the cavity 22c. Shaped member 3
(Specifically, the surface 3b opposite to the surface 3a) is in contact with the parting surface 21a.

Next, the molten resin for molding the injection molded article 1 is
The cavity 22c is injected and filled through a sprue and a runner communicating with the inner wall surface of the recess 22b. Since the molten resin is injected from an opening of a sprue (runner) provided on the inner wall surface of the concave portion 22b, the surface 3 of the sheet-like member 3 at the position of the cavity 22c on the concave portion 22b side is used.
It adheres complementarily only to a. Specifically, in the present embodiment, the sheet-shaped member 3 has a high melting point that does not melt at the temperature (about 130 to 200 ° C.) of the molten resin (the molten agglomerated resin) for molding the injection-molded article 1. It is made of material,
When the molten resin is injected and filled into the cavity 22c, a part of the molten resin
a into the fine irregularities.

In this embodiment, both parting surfaces 2
Although the air vent is not provided on 1a, 22a as described above, the air in the cavity 22c is a sheet-like member sandwiched between both parting surfaces 21a, 22a when the molten resin is injected and filled into the cavity 22c. 3 and outside the cavity 22c (outside the mold 20) via a gap due to interface mismatch between the parting surfaces 21a and 22a.
Is discharged.

More specifically, in the present embodiment, the sheet-like member 3 is formed of paper or the like as described above, and the surface roughness of the sheet-like member 3 is larger than the surface roughness of both parting surfaces 21a and 22a. With such a configuration, when the sheet-shaped member 3 is sandwiched between the two parting surfaces 21a and 22a, a gap is generated between the sheet-shaped member 3 and the parting surfaces 21a and 22a. When the molten resin is injected, the air or the volatile gas (hereinafter, referred to as “air”)
It is configured such that the “air” is efficiently discharged out of the cavity 22c, and the cavity 22c is completely filled with the molten resin. That is, in the present embodiment, by changing the material and the like (surface roughness and the like) of the sheet-like member 3 in advance, the size of the gap due to the interface mismatch is adjusted, and the air in the cavity 22c is efficiently discharged. In order to improve the efficiency of discharging air from the cavity 22c, air vents are formed on the parting surfaces 21a and 22a of the mold 20 and grooves of the air vents are formed. Since the fine adjustment of the depth is not required, the cost for forming the mold 20 is reduced.

On the other hand, when the molten resin is injected and filled as described above, the molten resin (injection molded article 1) is cooled and solidified, and then the mold movable section 21 is moved in the direction A ′ (the metal mold). (Partition surface 21a, 22a) is separated to open the mold, and then the injection molded article 1 and sheet member 3 are moved from the recessed part 22b and the parting surface 22a. Take out.

In this embodiment, the sheet-like member 3 (the portion where the injection-molded article 1 is not attached) is picked and pulled by an arm member (not shown) or the like arranged near the injection-molded article 1 to be taken out. Thereby, the injection-molded article 1 and the sheet-like member 3 which are integrated are taken out.

That is, during the step of injecting and filling the molten resin into the cavity 22c, a part of the molten resin is in a state of entering the fine irregularities on the surface 3a of the sheet-like member 3, so that the molten resin When the (injection molded article 1) is solidified, the injection molded article 1 and the sheet member 3 are in an integrated state. When the sheet member 3 is picked and pulled as described above, the sheet The injection molded article 1 integrated with the member 3 can be easily taken out.

That is, in the conventional manufacturing method, when the injection molded article 1 made of the agglomerated resin is molded, the cavity 22 is formed due to the adhesiveness of the surface of the agglomerated resin.
Although the injection molded article 1 could not be easily taken out from the injection molded article 1 from the cavity 22c in the present embodiment, even when the injection molded article 1 made of the agglomerated resin was molded, The injection-molded article 1 can be molded so that it can be easily taken out. In particular, in the present embodiment, when removing the injection-molded article 1, the injection-molded article 1 can be removed by the amount that the injection-molded article 1 does not have to be directly picked by an arm member or the like.
It is also possible to prevent dirt and the like from adhering to the surface of the substrate.

On the other hand, when the injection-molded article 1 and the sheet-shaped member 3 are taken out as described above, the sheet-shaped member 3 is moved downward, and the previous injection-molded article 1 (molten resin) is removed. In the case of injection etc., both parting surfaces 21a, 22a
Another portion of the sheet-like member 3 not arranged between the two parting surfaces 21a and 22a is arranged.

More specifically, the above-described gear having projections passed through some of the through holes 5a and 5b is rotated by a predetermined angle, and the sheet-like member 3 wound around the core member 7 is rotated. Is further extended downward, and the through holes 5a, 5b, which are different from the through holes 5a, 5b through which the projection pieces of the gear have been passed up to this point.
5b through the protruding piece of the gear, the other through-hole 5a,
5b is positioned, and the sheet member 3 is positioned with respect to the mold 20.

After positioning another portion of the sheet-like member 3 between the two parting surfaces 21a and 22a in the same manner as described above, that is, the sheet is placed between the two parting surfaces 21a and 22a. Repeating the step of sandwiching the sheet member 3, the step of injecting and filling the molten resin into the cavity 22c, the step of taking out the injection molded article 1 and the sheet member 3, and the step of moving the sheet member 3 by rotating the gears. Thereby, a desired number of injection molded articles 1 are molded.

In this embodiment, as described above, before the injection and filling of the molten resin (the injection molded product 1), the through holes 5a and 5b (extended, the sheet-like member 3) are formed using gears. Since the positioning is performed with respect to the two parting surfaces 21a, 22a, etc., the adhesion position of the molten resin (the injection molded article 1) to the sheet-like member 3 is stably set to a desired position according to the rotation angle of the gear, and the fixed length The number of the molten resin (the injection molded article 1) adhered to the sheet member 3 can be controlled to a constant number.

In the present embodiment, the sheet-like member 3 is formed as a tape-like member, so that the positioning of the through holes 5a and 5b as described above is performed.
Is required to move in only one direction (the longitudinal direction of the sheet-like member 3), compared to a case where the sheet-like member 3 must be moved in multiple directions when the sheet-like member 3 moves. The movement efficiency of the sheet-shaped member 3 (and thus the production efficiency of the injection-molded article 1) is improved, and a mechanism for moving the sheet-shaped member 3 (a mechanism including the above-described gears) is realized as a simple one.

In this embodiment, a plurality of injection-molded articles 1 are integrated with one sheet-shaped member 3 by the above-described manufacturing method. Each injection-molded product 1 is configured to be easily peeled off from the sheet-like member 3 only with the hand force of an operator or the like. That is, the molten resin (injection molded article 1) in the above-described production method
After the injection-molded article 1 is molded, the injection-molded article 1 can be easily peeled off only by the hand force of an operator or the like, after the injection-molded article 1 is molded. When the injection-molded article 1 is packed and transported, the injection-molded article 1 and the sheet-shaped member 3 are integrated, while the injection-molded article 1 is actually used. The product 1 and the sheet-like member 3 are configured to be used in a state where they are separated from each other.

As described above, in this embodiment, a plurality of injection molded articles 1 are integrated with one sheet-shaped member 3 by the above-described manufacturing method. When packing the injection-molded article 1, the plurality of injection-molded articles 1 can be handled as one unit via one sheet-like member 3. Therefore, according to the present embodiment,
Work such as packing of the injection molded article 1 can be performed efficiently.

In the case where the length of the sheet-like member 3 to which the plurality of injection-molded articles 1 are attached is too large as compared with the width of a case (not shown) for packing the injection-molded articles 1, etc. , The sheet-like member 3 is bent at an appropriate place as appropriate,
It is also possible to pack the injection molded article 1 and the sheet-like member 3 by cutting or the like.

In this embodiment, since the injection molded article 1 is manufactured so that the injection molded article 1 adheres only to one surface 3a of the sheet member 3, the injection molded article 1 can be easily handled after molding. become. That is, although the injection molded article 1 is made of the agglomerated resin, it has an adhesive surface, but the surface 3b of the sheet member 3 on which the injection molded article 1 is not attached.
Function as a partition in the case for packing the injection-molded article 1 and packing such that another injection-molded article 1 contacts only the surface 3b, thereby preventing the respective injection-molded articles 1 from sticking to each other. Since it is possible, it is not necessary to separately prepare a partition for preventing the respective injection molded products 1 from sticking to each other, so that the handling of the injection molded products 1 becomes easy.

In the above description, both parting surfaces 21
The step of sandwiching the sheet-like member 3 between a and 22a corresponds to the sheet-like member sandwiching step of the present invention, and the step of injecting and filling the molten resin into the cavity 22c corresponds to the injection step of the present invention. The step of removing the molded article 1 and the sheet-shaped member 3 corresponds to the molded article removing step of the present invention, and the step of moving the sheet-shaped member 3 by rotating the gear corresponds to the sheet-shaped member moving step of the present invention. .

The embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment.
Various embodiments can be adopted. For example, in the above embodiment, when packing the injection molded article 1 after molding, the sheet-shaped member 3 is described as functioning as a partition for partitioning each injection molded article 1, but as shown in FIG. Further, the injection molded product 1 may be packed and the like after applying the cover member 31 covering the injection molded product 1.

Specifically, for example, first, a cover member 31 having a plurality of concave portions 33 capable of covering each injection molded article 1 attached to one surface 3a of the sheet member 3 is prepared in advance. (See FIG. 3). Then, after the molding of the plurality of injection molded products 1 by the manufacturing method of the above embodiment is completed, the cover member 31 is covered on each injection molded product 1 so that each injection molded product 1 fits in the plurality of recesses 33. Then, the contact surface 31a of the cover member 31 with the sheet member 3 and the sheet member 3 are bonded with an adhesive or the like.

In this manner, the injection molded product 1
At the time of storage of the injection-molded article 1, another article collides with the injection-molded article 1 and the surface of the injection-molded article 1 is scratched. The surface can be reliably prevented from being soiled. Note that the step of covering the injection molded article 1 with the cover member 31 as described above corresponds to the cover member mounting step of the present invention.

On the other hand, in the above embodiment, the injection molded article 1 is described as being made of the agglomerated resin, but the injection molded article 1 is made of another material to which the injection molding method can be applied. Of course, it may be. For example, thermoplastic resins such as polyolefin-based elastomer, polystyrene (PS) -based elastomer, thermoplastic polyurethane (TPU) -based elastomer, unsaturated polyester (UP) -based elastomer, and styrene-ethylene-butylene-styrene block copolymer (SEBS) -based elastomer are used. It can be suitably used as a resin for molding an injection molded article 1. These thermoplastic resins (injection molded article 1) may be constituted as a low-hardness material (low-hardness material having an A-type hardness of 40 or less according to JIS K6253) as required, or the low-hardness material may be used. A material having a higher hardness than the material may be used.

When the injection-molded article 1 is molded using a material having sufficiently higher hardness than the low-hardness material, the injection-molded article 1 cooled and solidified in the cavity 22c is used.
When taking out, it is also possible to take a method of projecting the injection molded article 1 itself and projecting it out of the cavity 22c with a pin (not shown) or the like. In other words, the problem that the direction in which the injection molded article 1 is projected by the ejection pin or the like (the direction in which the injection molded article 1 is dropped from the mold 20) is not stabilized does not occur.

The material of the sheet member 3 is made of polyethylene terephthalate (PET), polycarbonate (P
C), polystyrene (PS), polyethylene (PE),
Polyamide (PA), thermoplastic polyurethane (TP
U), a resin material such as a thermoplastic elastomer (TPE) or the like, or by laminating a plurality of sheet pieces having different materials (for example, the injection molded product 1).
From the surface 3a side to which a first sheet made of polyethylene (PE), polymethyl methacrylate (PMMA), etc., a second sheet made of polyamide (PA), polyethylene terephthalate (PET), aluminum sheet, etc., a double-sided tape, The sheet-shaped member 3 may be formed by sequentially laminating a third sheet made of a hook-and-loop fastener, a sponge material, or the like. When the sheet-like member 3 is made of a resin material or the like, the sheet-like member
If necessary, a textured surface, an uneven surface, and a hole are formed on the surface of the sheet-shaped member 3 so as to form a gap (a gap for air discharge) due to interface mismatch between the parting surfaces 21a and 22a. , Grooves and the like are preferably formed. Depending on the hardness of the sheet-like member 3, it may not be possible to wind one end of the sheet-like member 3 around the core material 7 as in the above embodiment, but in such a case, the predetermined length is required. By appropriately arranging the sheet-shaped member 3 between the parting surfaces 21a and 22a, the injection molded article 1 can be molded in the same manner as in the above embodiment.

Here, in the case where the material of the sheet-like member 3 is a resin material as described above, the cavity 22c
The molten resin is injected and filled into the sheet-like member 3.
May be configured so that the molten resin and the sheet-like member 3 are mutually welded when they adhere to each other in a complementary manner.

In this case, after the injection-molded article 1 is molded, the injection-molded article 1 and the sheet-shaped member 3 are stably fixed. However, even in actual use, it is possible to adopt a usage mode in which the injection molded article 1 and the sheet-shaped member 3 are integrated. In this embodiment, the sheet-shaped member 3 is appropriately cut according to the use of the injection-molded article 1, and the number of the injection-molded article 1 to be applied in actual use, the width and the length of the sheet-shaped member 3, and the like. Should be changed.

As described above, in order for the injection molded article 1 and the sheet member 3 to be stably fixed,
When the sheet-like member 3 is clamped between the parting surfaces 21a and 22a and the sheet-like member 3 is sandwiched between the two parting surfaces 21a and 22a, the sheet-like member 3 disposed at the cavity 22c position
Is provided with a through-hole (not shown) extending from one surface 3a to the other surface 3b so that the molten resin
When the resin 2c is injected and filled, the molten resin may adhere to both surfaces 3a and 3b of the sheet member 3 through the through holes.

In this way, regardless of whether or not the injection molded article 1 is welded to the sheet member 3,
The injection-molded article 1 and the sheet-like member 3 are stably fixed by the portions of the injection-molded article 1 attached to the both surfaces 3a, 3b through the through holes in.

To ensure that the injection molded article 1 is adhered to both surfaces 3a and 3b of the sheet member 3, the sheet member 3 located at the cavity 22c as in the above embodiment is parted. It is desirable to keep the state away from the surface 21a. On the other hand, the parting surface 21
a, 22a to clamp both parting surfaces 21a, 2
When the sheet-like member 3 is sandwiched between 2a
It is also possible to adopt a mode in which the portion of the sheet-shaped member 3 arranged at the position c is deformed (stretched) by the molten resin injected and filled into the cavity 22c.

More specifically, first, for example, a recess (hereinafter referred to as “movable portion side recessed portion”) is provided in a part of the parting surface 21a opposite to the recessed portion 22b, and is arranged at the position of the cavity 22c. The part of the sheet-like member 3 to be formed is arranged at a position away from the parting surface 21a.

Further, the material of the sheet-like member 3 is constituted so as to be capable of expanding and contracting (in other words, having extensibility) or to be softened so as to be deformable by heating, and the molten resin is injected into the cavity 22c. At the time of filling, the portion of the sheet member 3 arranged at the cavity 22c is pressed and deformed to the inner wall surface of the movable portion side concave portion by the injection pressure of the molten resin. When the injection-molded article 1 and the sheet-like member 3 are taken out after the mold is opened, a dent on the sheet-like member 3 deformed into a shape corresponding to the shape of the movable-portion-side concave portion (hereinafter referred to as a “sheet-side Injection molding 1)
Is partially settled, and the inner wall surface (sheet-shaped member 3) of the sheet-side recessed portion and the injection-molded article 1 are complementarily attached to each other. In the case where the sheet-like member 3 is configured to be deformably softened by heating, the sheet-like member 3 is heated before the injection of the molten resin so that the sheet-like member 3 is deformed as described above.

In this way, the surface of the injection-molded article 1 can be stained or scratched during storage of the injection-molded article 1 by the portion covered by the inner wall surface of the concave portion on the sheet side. The effect is obtained that it becomes difficult to attach. On the other hand, in the above embodiment, in order to set the attachment position of the injection-molded article 1 to the sheet-shaped member 3 at a desired position, the projection piece of the gear is passed through the through holes 5a and 5b on the sheet-shaped member 3. Although the positioning of the through holes 5a and 5b (extended and the sheet member 3) is performed, an appropriate mark (by printing or the like) of the sheet member 3 is provided on the sheet member 3 instead of the through holes 5a and 5b. A mark may be provided on the front surfaces 3a, 3b), and the position of the sheet member 3 may be determined by detecting the position of the mark by a method such as image recognition. In this case, the mark corresponds to a positioning mark.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an injection-molded product and a sheet-like member formed by a manufacturing method according to an embodiment.

FIG. 2 is an explanatory view illustrating a method for manufacturing an injection-molded product of an example.

FIG. 3 is a cross-sectional view showing a state in which a cover member is put on the injection molded product of the example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Injection molded article, 3 ... Sheet-shaped member, 3a ... Surface, 5a,
5b: Through-hole, 20: Mold, 21: Mold movable part, 21
a, 22a: Parting surface, 22: Mold fixing part, 22
b: recessed portion, 22c: cavity, 31: cover member,
33 ... recess

Claims (7)

[Claims] 1. An injection molded product in which an injection molded product is formed by injecting a molten resin into a mold cavity after clamping a mold fixed side and a mold moving side on both parting surfaces. In the manufacturing method, a sheet-shaped member made of a material different from the molten resin is sandwiched between the parting surfaces of the mold when clamping the mold, and a part of the sheet-shaped member is positioned at the cavity position. And a step of injecting the molten resin into the cavity after the sheet-shaped member sandwiching step, and disposing a part of the molten resin filled in the cavity at the position of the sheet in the cavity position. A gap that is caused to adhere complementarily to a member and that air in the cavity is caused by an interface mismatch between the sheet-like member and the parting surface sandwiched between the parting surfaces; An injection step of discharging the injection molded article to the outside via a mold, and after the injection step, a molded article taking out step of taking out the injection molded article cooled and solidified in the cavity and the sheet-shaped member by opening the mold. A method for producing an injection-molded article, comprising: 2. In the sheet-like member holding step, a portion of the sheet-like member arranged at the cavity position is arranged along the parting surface, and in the injection step, the cavity The method for manufacturing an injection-molded article according to claim 1, wherein the molten resin is attached to only one surface of the sheet-shaped member at a position in a complementary manner. 3. After the molded product taking-out step, the sheet-shaped member is moved with respect to the mold, and in the sheet-shaped member holding step, between the mold fixed side and the mold moving side. A sheet-like member moving step of disposing another part of the arranged sheet-like member between the opened mold fixed side and the mold moving side where the mold is opened; The method for manufacturing an injection-molded article according to claim 1 or 2, further comprising a step similar to the sheet-shaped member holding step, the injection step, and the molded article removing step after the moving step. 4. A positioning mark is formed on the sheet-like member. In the sheet-like member moving step, the positioning after the movement of the sheet-like member is performed by positioning the positioning mark. The method for producing an injection-molded product according to claim 3, wherein: 5. The method according to claim 3, wherein the sheet-shaped member is a tape-shaped member. 6. The method for producing an injection molded product according to claim 1, wherein the hardness of the injection molded product is 40 or less in JIS A type hardness. 7. A cover member having a concave portion corresponding to the shape of the injection molded product is prepared, and after the molded product removing step, the cover member is injected so that the injection molded product fits in the concave portion. The method for producing an injection-molded article according to any one of claims 1 to 6, further comprising a cover member mounting step of covering the molded article.